Process and apparatus for the manufacture of pile fabrics

ABSTRACT

Improvements in the art of making pile fabrics by needle looming a non-woven fabric. The conventional needle loom is modified to use needles in which the conventional barbed end is replaced with a knife edge end so that a filament or fiber pushed out of the non-woven fabric by the needle is cut as the needle reaches its maximum throw between the needle knife edge and an anvil means placed below the tufting plate. The anvil means provides a surface against which to cut the filaments or fibers which are needled into the &#39;&#39;&#39;&#39;pile&#39;&#39;&#39;&#39; position at substantially uniform pile length. A disposable material such as paper or the like may be disposed on the anvil for the needle and knife edge to bear against.

United States Patent [191 Griiber [45] Apr. 10, 1973 [5 PROCESS ANDAPPARATUS FOR THE 3,579,763 5 1971 Sommer ..28/722 R MANUFACTURE OF PILEFABRICS [76] Inventor: Adolf Wilhelm Griiber, Thuringer Str. 1,Waid-Ofling/Bergstr., Germany [22] Filed: Aug. 26, 1971 [21] Appl. No.:175,112

[30] Foreign Application Priority Data Sept. 2, 1970 Germany ..P 20 43465.5

[52] U.S. Cl. ..28/4 R [51] Int. Cl. ..D04h 15/00 [58] Field of SearchZS/72.2 R, 4 R

[56] References Cited UNITED STATES PATENTS 3,451,109 6/1969 Klein.28/72.2 R

Primary Examiner-Louis K. Rimrodt Att0rneyRalph D. Dinklage et al.

[ ABSTRACT Improvements in the art of making pile fabrics by needlelooming a non-woven fabric. The conventional needle loom is modified touse needles in which the conventional barbed end is replaced with aknife edge end so that a filament or fiber pushed out of the nonwovenfabric by the needle is cut as the needle reaches its maximum throwbetween the needle knife edge and an anvil means placed below thetufting plate. The anvil means provides a surface against which to cutthe filaments or fibers which are needled into the pile position atsubstantially uniform pile length. A disposable material such as paperor the like may be disposed on the anvil for the needle and knife edgeto bear against.

9 Claims, 5 Drawing Figures 1 PROCESS AND APPARATUS FOR THE MANUFACTUREOF PILE FABRICS This invention relates to pile fabrics. It moreparticularly refers to pile fabrics made by needling a continuousfilament or staple fiber non-woven fabric.

The needling of non-woven fabric is a generally known operation which iscarried out on a commercially available piece of equipment called aneedle loom. In the operation of needle looms, a bed of barbed needlesis worked in reciprocating fashion transverse to the major surface of apre-formed non-woven fabric so as to displace some of the staple lengthfibers of the fabric, or some portions of continuous fila'rnents of suchfabric, into a position which is transverse to the major fabricsurfaces. The barb on the needle end causes fibers to be displaced whenthe needle is being moved both toward and away from the fabric. Thepurpose of needling is generally to increase the delamination resistanceof non-woven fabrics.

A needle loom is usually composed of a needle bed with a multiplicity ofneedles, generally having barbed ends, extending normal thereto; meansto move the needles and needle bed in a reciprocating motion generallyparallel to the needle axis; a hold-down plate with apertures thereingenerally corresponding to the needles through which the needles pass; atufting plate spaced from and generally parallel to the hold-down platewith apertures therein corresponding to the needles through which theneedles pass; and means to dispose a fabric to be needled between thehold-down plate and the tufting plate.

A needle loom conventionally operates by positioning a pre-formedfabric, preferably a non-woven fabric, between the hold down plate andthe tufting plate of the loom and reciprocating the needle board andbarbed needles thereon into and out of engagement with the fabric.Usually the fabric is a continuous fabric which is moved through theneedle loom in an intermittent motion consistent with the reciprocationof the needles;

ln passing through the non-woven fabric, the needles impale or otherwiseforce one or more fibers or portions of continuous filaments out oftheir conventional alignment generally parallel to the major surfaces ofthe fabric to a position generally transverse to the plane of thesemajor fabric surfaces so as to prevent or retard delamination.

In making pile fabrics by the needling of non-woven fabrics, the needlesare so sized, positioned and operated that they are not barbed. Theseneedles are caused to pass completely through the non-woven fabric andpush fibers or portioniof continuous filaments out past one of the majorsurfaces of the nonwoven fabricinto a position generally normal theretobut not to pull any fibers back in the other direction. These normalfibers ortilament portions are the pile portion of the fabric.

It is known in the prior art to produce rather hard floor coverings bycarrying out the tuftingyof a nonwoven fabric via a needle loom and thenfully impregnating the pile fabric thus obtained with a suitable bindingagent which is then dried and set up in the usual manner. Such floorcoverings are commercially available on the open market.

It is also known that softer floor coverings, that is carpets or carpettiles, can be made, according to German Gebrauchsmuster No. 1,989,434,by limiting the impregnation of such needled, tufted non-woven fabricsto about two-thirds of the thickness thereof from the non-pile sidethereof, that is from the side which afterward will face the floor. Theupper third of the fabric remains free of bonding agent so that a softtread layer is thus achieved. Such carpeting is commercially availableon the open market.

If it is desired to produce loop type carpeting, it is known tosubstitute forked needles for conventional straight needles wherebyportions of filaments or fibers are pushed out of the fabric in a loopor folded configuration. Such loop carpeting is commercially availableon the open market.

The carpeting materials which are obtained by the two last-describedprocesses do present a pleasing ap pearance, but when used as floorcoverings they prove to be extremely difficult to clean, :itbeingespecially difficult to remove wood chips, Christmas tree needlesand other particles. For this reason, consumers of woven or tufted floorcoverings are more likely to purchase a more open pile type of fabric,in which the tops of the loops are cut, even though this type of fabricis more costly. This cut pile type of structure can also be achieved ina needle tufted non-woven fabric type of pile material by performing anespecially deep needling with the classical needles, possibly subjectingthe needled fabric to napping the loop surface thus produced, and thensubjecting the looped pile surface to a shearing process like that usedin the manufacture of velours. Although this process produces a goodproduct, it is not particularly desirable because it requires aplurality of expensive process steps and because there is a significantmaterial loss in the shearmg process.

' It has been proposed to produce such sheared type of pile fabrics by asort of combination of some of the techniques described above (seeFrench Pat. No. 1,528,749). According to this reference, forked needlesare used to needle continuous filament non-woven fabric. The needles areso dimensioned-and operated that they stretch portions of continuousfilaments past their elastic limit and therefore break the loops thuspushed out of the base non-woven fabric. Since not all continuousfilaments in the same non-woven fabric have the same ultimate tensilestrength, this procedure" results in a product having a rather randomlength pile.

While this may be acceptible for certain end use products, it is by nomeans satisfactory for all carpet applications.

-It is therefore an important object of this invention to provide anovel process and apparatus for the produc- 1 tion of pile fabrics fromnon-woven fabrics.

It is another object of this invention to provide a 1 isting needlelooming apparatus by providing a knife edge on the needle end so as tobe able to cut the filament or fiber loops as they are pulled out of thenonwoven fabric against an anvil means which is disposed on the side ofthe tufting board away from the holddown board. In a preferredembodiment of this invention, means is provided for limiting the throwof the reciprocating needles so that the knife edge end thereof justbarely touches, or just barely misses, the abovereferred-to anvil meanswhereby cutting the filament loops between the knife and the anvil.

The improved process of this invention utilizes the above apparatus inthe following manner: the needles engage individual staple fibers,preferably of about 4 to 10 mm in length continuous filaments orportions thereof and push them out of the base fabric into a loopy pileconfiguration; as the needles extend to the limit of their throw,carrying a filament or fiber portion on the end thereof, the knife edgeend thereof approaches an anvil means until they juxtapose with thefilament loop therebetween such that the loop is severed, usually at themaximum extension of the needle throw. Thus all of the pile filamentportions have a uniform height without the inconvenience of eitherhaving a loop pile construction or a shearing operation with attendantinefficiencies.

Understanding of this invention will be facilitated by reference to theaccompanying drawing in which:

FIG. 1 is an isometric, schematic view of a needlelooming operation andapparatus in accord with this invention;

FIG. 2 is a sectioned elevation of the operation of one needle of theloom of FIG. 1 at the maximum throw position;

FIG. 3 is an elevation of a needle for use in this invention;

FIG. 4 is an enlarged view of the needle knife edge; and

FIG. 5 is similar to FIG. 4 showing a different knife edge construction.

Referring now to this drawing, and more particularly to FIG. 1 thereof,a fabric 1, suitably composed of nonwoven fibers or filaments, is fedfrom a source (not shown) by means of a conveyor belt 2, or othersimilar means, into a needle loom. The needle loom comprises a needleboard 3 with a multiplicity of needles 4 extending parallel to eachother normal to the needle board; a tufting board 7, with a multiplicityof apertures 8 therein aligned with the needles 4 and the hold-downboard apertures 6, generally parallel to and spaced from the hold-downboard 5 on the side thereof away from the needle board 3; a means 9 forreciprocating the needle board 3 and attendant needles 4 into and out ofengagement with the fabric 1 through the apertures 6 and 8; and take-upmeans 10 for the needled pilefabric 11 emerging from the needle loom.

The needles 4 used in the needle .loom of this invention are shown inFIGS. 3, 4 and S and have an angled shank 12 terminating in a narrowblade 13 which blade 13 has a knife edge 14 on the end thereof. Theknife edge 14 may be flat as shown in FIG. 4 or it may be hollow groundas shown in FIG. 5.

According to this invention, an anvil means 15 is provided in the needleloom. This anvil means is disposed on the side of the tufting board 7away from the holddown board 5. It is composed of an anvil 15 and,preferably, an anvil band 16 positioned on the needledirected side ofthe anvil. The anvil band 16 may be a disposable film or layer ofrelatively soft material such as paper, paper board, plastic or thelike. The cutting of the fiber or filament loops is actuallyaccomplished between the knife edge end 14 and the anvil band 16.

It is within the spirit and scope of this invention to utilize aconstantly or intermittently moving anvil band 16. This can beaccomplished by having a feed roll 17 of paper or the like; passing thefed paper 16 over a guide roller 18 into appropriate position, takingthe used paper out of the anvil means over a roller 19 and winding it upon a take-up roll 20. The paper 16 may be moved by means of a hand crank21 or by any other conventional motive means keyed to the movement ofthe fabric and/or the operatIon of the needle loom or not as the casemay be.

According to this invention, a generally conventional needling machinemay be used but it should preferably be of sturdy construction. Theneedle ends should have a cutting edge 0.5 to 2 mm wide. The needleboard, tufting board and hold-down board are drilled in strictgeometrical alignment to achieve a uniformly dense pattern, a uniformlyoffset arrangement with a spacing of, for example, 7 mm on the centersof the holes being technically feasible. A denser spacing, down to 4 mmfor example, may be desirable, and requires extreme precision in themanufacture of the parts and the needles must be very straight. A widerneedle spacing is, of course, conceivable, especially when heavy fibersare involved, but wider needle spacing results in relatively coarse pilestructures. The offset arrangement of the needles means that the spacingbetween the needle wales in the finished product will be equal to halfof the needle-to-needle distance in the needle board (3.5 mm in ourexample). The anvil band is preferably transported at a velocity that isindependent of the production velocity, (e.g., from 0 to 5 m/min).

During the needling process the needles 4 first penetrate the hold-downboard 5, then the fabric 1, from which they push fiber clusters 22 downthrough the tufting board 7. As soon as the cutting edge of the needlecontacts the surface of the anvil band 16 and slightly penetrates intothe latter, the fibers of the fiber clusters are severed. The sharpnessof the cutting edges is preferably such that until they encounter theanvil band the needles will produce a perfect loop without appreciablefiber damage, and the loop will not be severed until the cutting edgecooperates with the anvil band.

The position of the anvil 15 is fixed in the machine in accordance withthe needle length in such a manner that it is not quite contacted by theknife edge end of the needle at the bottom dead center of the movement(maximum needle throw). This prevents unnecessary dulling of the cuttingedges. The length of the cut pile in the carpeting is determined by theneedle length, the spacing between the tufting plate and the anvil meansand the needle throw.

The cut pile-like structure of the needled carpeting produced in thismatter is achieved without loss of material.

Partial impregnation, addition of bonded padding and back coating areall conventional carpet making operations which can be performed bymethods well known in the art.

It is within the scope of this invention to utilize as the non-wovenfabric, a continuous filament or staple fiber non-woven fabric which hasbeen subjected to a needling process whereby positioning portions of thefiber or filaments thereof transverse to the plane of the major surfacesthereof but retained within the overall fabric structure, that isneedled but not tufted nonwoven fabric.

What is claimed is:

1. In a needle loom comprising means for feeding non-woven fabricthereinto, means for removing needled, non-woven fabric therefrom, aneedle board, a multiplicity of needles extending generally parallel toeach other and normal to said needle board, a holddown board withapertures therein corresponding to said needles positioned to receivesaid needles therethrough, a tufting board with apertures thereincorresponding to said needles which tufting board is normally. spacedfrom said hold-down board sufficient to pass said non-woven fabrictherebetween, and means for moving said needles through said aperturesrelative to said non-woven fabric whereby forcing portions of fibers ofsaid fabric to become aligned substantially normal to the major surfaceof said fabric; the improvement which comprises the fabric-directed endsof said needles being a knife edge and an anvil means juxtaposed themaximum throw position of said needles whereby cutting said fiberportion between said knife edge and said anvil means at substantiallythe same individual pile fiber portion height.

2. The improved apparatus as claimed in claim 1, in cluding means forintermittently moving said nonwoven fabric through said needle loom.

3. The improved apparatus as claimed in claim 1 wherein said anvil meanscomprises an anvil and an anvil band, and wherein said anvil means isspaced from said tufting board a distance such that said needle knifeedge contact said anvil band and do not contact said anvil.

4. The improved apparatus claimed in claim 3 wherein said anvil band isa disposable, soft material selected from the group consisting of paper,paper board and plastic.

5. The improved apparatus claimed in claim 5, including means forfeeding said anvil band to said needle loom and means for removing suchtherefrom.

6. The improved apparatus as claimed in claim 1 wherein said knife edgeend is 0.5 to 2 mm wide.

7. Process of forming pile carpeting comprising a non-woven fabriccomposed of fibers to a needle loom; pushing loops of portions of saidfibers out of said nonwoven fabric into a direction normal to a majorsurface of said fabric by reciprocating needles through said fabricnormal to said major surface; juxtaposing the fabric-directed end ofsaid needles to an anvil means; and cutting said fiber portions betweenthe knife edge and said anvil means at the substantially maximum throwof said needles.

8. Process as claimed in claim 7, including providing said anvil meansas a combination of a relatively hard anvil and a relatively soft anvilband and including bearing said knife edge only against said anvil band.

9. Process as claimed in c arm 8, including feeding said fabric to saidloom intermittently in synchronization with the reciprocation of saidneedles, utilizing as said anvil band a disposable material, and feedingsaid anvil band between said needles and said anvil at a rate'independent of the rate at which fabric is fed to said loom.

5 m UNITED s1? 'I I'ISILA'ITENT OFFICE?H?! 5 "J is!" CERTHKJML 01*QORRECHGN mum No. 3,725,984 Dated Agril 101 19 73 Adolf Wilhelm Graber IIt is certified that error appears in the above-identified patent atseid Letters Patent are hereby corrected as shown below:

Fm Front age Name of Assignee is missing. This .should read:

-'-Firmr=1 Carl Freudenberg Weinheim, Germany-- Signedand. sealed this1st day of January 19714..

(SEAL) y Attest: t 9' i EDWARD M.FLETGHER;JR. I RENE D. .TEGTD [EYERAttesting Officer- Acting Commissioner of Patents

1. In a needle loom comprising means for feeding non-woven fabricthereinto, means for removing needled, non-woven fabric therefrom, aneedle board, a multiplicity of needles extending generally parallel toeach other and normal to said needle board, a hold-down board withapertures therein corresponding to said needles positioned to receivesaid needles therethrough, a tufting board with apertures thereincorresponding to said needles which tufting board is normally spacedfrom said holddown board sufficient to pass said non-woven fabrictherebetween, and means for moving said needles through said aperturesrelative to said non-woven fabric whereby forcing portions of fibers ofsaid fabric to become aligned substantially normal to the major surfaceof said fabric; the improvement which comprises the fabric-directed endsof said needles being a knife edge and an anvil means juxtaposed themaximum throw position of said needles whereby cutting said fiberportion between said knife edge and said anvil means at substantiallythe same individual pile fiber portion height.
 2. The improved apparatusas claimed in claim 1, including means for intermittently moving saidnon-woven fabric through said needle loom.
 3. The improved apparatus asclaimed in claim 1 wherein said anvil means comprises an anvil and ananvil band, and wherein said anvil means is spaced from said tuftingboard a distance such that said needle knife edge contact said anvilband and do not contact said anvil.
 4. The improved apparatus claimed inclaim 3 wherein said anvil band is a disposable, soft material selectedfrom the group consisting of paper, paper board and plastic.
 5. Theimproved apparatus claimed in claim 5, including means for feeding saidanvil band to said needle loom and means for removing such therefrom. 6.The improved apparatus as claimed in claim 1 wherein said knife edge endis 0.5 to 2 mm wide.
 7. Process of forming pile carpeting comprising anon-woven fabric composed of fibers to a needle loom; pushing loops ofportions of said fibers out of said non-woven fabric into a directionnormal to a major surface of said fabric by reciprocating needlesthrough said fabric normal to said major surface; juxtaposing thefabric-directed end of said needles to an anvil means; and cutting saidfiber portions between the knife edge and said anvil means at thesubstantially maximum throw of said needles.
 8. Process as claimed inclaim 7, including providing said anvil means as a combination of arelatively hard anvil and a relatively soft anvil band and includingbearing said knife edge only against said anvil band.
 9. Process asclaimed in claim 8, including feeding said fabric to said loomintermittently in synchronization with the reciprocation of saidneedles, utilizing as said anvil band a disposable material, and feedingsaid anvil band between said needles and said anvil at a rateindependent of the rate at which fabric is fed to said loom.